By default, Windows Vista Defragments System files whenever you start the PC. However, with automatic weekly defragmentation Vista, this feature is unnecessary. All the more it slows down the startup of Windows Vista.
- To disable, click the Start button, type regedit in the search box and press the Enter key.
- Pull down the HKEY_LOCAL_MACHINE, SOFTWARE, Microsoft, Dfrg, BootOptimizeFunction.
- Double click on the Enable.
- In the field Value data, type N in place of Y, click Ok.
- Close Registry Editor. The change will be effective from the next time you start your computer.